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Universities face a new competitor in the form of massive open online courses, or MOOCs. These digitally-delivered courses, which teach students via the web or tablet apps, have big advantages over their established rivals. With low startup costs and powerful economies of scale, online courses dramatically lower the price of learning and widen access to it, by removing the need for students to be taught at set times or places. The low cost of providing courses--creating a new one costs about $70,000--means they can be sold cheaply, or even given away. Clayton Christensen of Harvard Business School considers MOOCs a potent "disruptive technology" that will kill off many inefficient universities. "Fifteen years from now more than half of the universities [in America] will be in bankruptcy," he predicted last year.

The first MOOC began life in Canada in 2008 as an online computing course. It was 2012, dubbed the "year of the MOOC", that generated vatic excitement about the idea. Three big MOOC-sters were launched: edX, a for-profit provider run by Harvard and the Massachusetts Institute of Technology (MIT); Coursera, partnered with Stanford University; and Udacity, a for-profit co-founded by Sebastian Thrun, who taught an online computing course at Stanford. The big three have so far provided courses to over 12m students. Just under one-third are Americans, but edX says nearly half its students come from developing countries (see chart 2). Coursera's new chief executive, Richard Levin, a former president of Yale University, plans an expansion focusing on Asia.

For all their potential, MOOCs have yet to unleash a Schumpetarian gale of disruption. Most universities and employers still see online education as an addition to traditional degree courses, rather than a replacement. Many prestigious institutions, including Oxford and Cambridge, have declined to use the new platforms.

Nick Gidwani, the founder of SkilledUp, an online-course directory, compares the process to the disruption of publishing and journalism. Large publishers used to enjoy a monopoly on printing presses, subscriber bases and deals with advertisers. A proliferation of low-cost blogs, websites and apps means they no longer do. Even successful print products have had to take on aspects of their digital rivals' model. Mr Gidwani sees "scant hope for 200 professors, all delivering the same lecture".

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